WordPress SEO plugin Yoast

I’m getting this message from Google Webmaster Tools when it tries to look into the “/post-sitemap.xml” of the sitemap that is being generated by the WordPress SEO plugin:
“Sitemap contains urls which are blocked by robots.txt.”

I deleted the robots.txt file a few days ago and I’m still getting this message. I don’t have WordPress blocking robots in the settings and I don’t have nofollow clicked in any of the pugin settings and none of the pages or posts have nofollow in the meta tags. Also I think Google indexes the stories on the front page but then loses track of them when they become archived?

link to site

Thanks in advance